Method of producing coal-tar pitch.



snares earner oration.

JOHN F. LOVEJOY, OF NEW YORK, N. Y., ASSIGNOR OF ONE-HALF TO ABRAHAM STEIN,

' OF NEW YORK, N. Y.

METHOD OF PRODUCING- COAL-TAR PITCH.

Specification of Letters Patent. Application filed March 5,1906. Serial No. 304,343.

Patented Dec. 31, 1907.

To all whom it may concern: 1

Be it known that I, JOHN F. LovnJoY, a citizen of the United States, and a resident of New York, county of New York, and State of New York, have invented a new and useful Improvement in Methods of Producing Coal Tar Pitch, of which the following is a specification.

The aim of my invention is to produce from coal-tar the pitch adapted more especially for use in the manufacture of coal riquets. The desirable itch for this purpose should have a' mefting point higher than that of the ordinary itch of commerce,

and should be free from t e fine particles of carbon, known as free carbon, and from other foreign matters which are usually contained in the original tar.

Heretofore, in the distillation of tar, the presence of water has been considered highly objectionable and it has been the general practice, before'distillation, to remove from the tar the water and the ammoniacal fluids, commonly present in smallpercentages, as far as practicable.- I have discovered the fact that, contrary to the general belief, the presence of water in the tar during distilla:

i tion is highly advantageous, provided it is 'used in substantial quantity.

In carrying out my rocess Isubjeot the tar to distillation in t e presence of water and subject to agitation, preferably passing steam u ward through the mass after it has acquire a temperature of 220 degrees Fab-- renheit, or therea-bout.

In ractice, I introduce into a still or re tort 0 any suitable construction from five toten parts by weight of water, and then introduce one hundred parts of crude tar, which is preferably heated before its introduction, in order to facilitate the operation. The mass. is graduallyheated to 212 degrees Fahren heit to distil or vaporize the water, care being taken to see that there is no violentboiling or foaming action.

tinned until a much higher temperature is attained. When the water has been. partially vaporized and the temperature ,begins.

to rise a preciabl y above the boiling point of water, t e heat is increased and the temper from 300 to 340 degrees Fahrenheit.

During this action, the mass may be advantageously agitated mechanically, and this agitation may be conthe tar, and that during the distilling operation, the resulting steam or vapor rising through the mass of tar, aids in causing a continuous agitation'and circulation of the same, and has a peculiarly eflicientaction in washing out, setting free and carrying away the particles of free carbon and other impurities, It also has the effect of thoroughly washing from the tar the ammoniacal liquor and of setting free and carrying away to a'substantialextent the light oils,

even'while the temperature of .the mass remains at or near 212 degrees Fahrenheit. The agitation of the tar, with which the Water 1s intermingled or mechanically combined, results in the steam or vapor coming in contact with and acting upon every portion of the tar, with the cleansing effect, and also in the vaporization and release of the various lighter oils so .that they may escape successively at their respective vaporizing temperatures as the distillation progresses,

The water will not be completely volatilized until the temperature of the mass has reached The distillation should, however, be carried on slowly in order to permit the oils to escape successively. The distillation is concluded at a-temperature offrorn 575 to 680 degrees Fahrenheit.

' The pitch resulting from my method of distillation will commonly have a melting oint of from 155 to 165 degrees Fahrenheit. nder ordinary conditions, the com 'lete distillation is accomplished in about th1rty six.hours, more or less, and the temperature standing near 212 degrees at the first twentyfour hours or thereabout. I

I believe myself. to be the first to intentionally add water ,to tar prior to or during the process of distillation, audit is to be understood that my invention relates to the employment of water alone to the exclusion of chemicals whichhave, in some instances been employed. r

The apparatus for practicing my invention may be of any suitable construction,

It is to be understood that I add water in a quantity which forms a substantial ortion of the entire charge ,a quantity which will produce a very great volume of steam.

I am aware that it has been proposed to distil coal tar in the presence of sulfate of iron, water being used in alimited quantity to dissolve the sulfate, but in practice it has been discovered that although the iron is beneficial in certain ways, it is seriously objectionable' because of its precipitation in the still beneath the tar, resulting in serious injur to-the still and in irregular and uncertain distillation. O

- Having described my invention, what I claim and desire to secure by Letters Patent is: i

1. The method of roducing pitch, consisting in distilling coa tar in the presence of an abnormal percentage of water.

2. The method of producing pitch, consisting in combining c0al-tar and water in substantially the proportions specified and distilling the same, at the same time subjecting the mass to agitation.

3. The method of producing pitch, con-- sisting in commingling coal-tar with a substantial percentage of water to the exclusion of other substances, and subjecting the mass to distillation until the resulting itch has a melting oint of 155 degrees ahrenheit, more or ess.

4. The method of roducing pitch, consisting in distilling coa -tar in the presence of an abnormal amount of water, and steam through the mass during disti lation.

'5. The method of roducing pitch, con

sisting in distilling coa -tar in the presence of assing' an abnormal amount of water, mechanically agitating the mass during distillation to insure distribution of the water through the mass and at the same time pass'ingsteam upward through the mass.

6. The method of producing pitch, consisting in commingling coal-tar and water, subjecting the mass to a tem erature of about 212 degrees Fahrenheit or twentyfour hours, more or less, and thereafter gradually raising the tem erature to from -57 5 to 680 degrees Fahren eit.

7. The method of producing pitch, consisting in distilling coal-tar and water in the proportionsgof .one hundred parts of tar more or less, and from five to ten parts 0 water, and subjecting the mass during distillation to mechanical agitation.

' In testimonywhereof I hereunto set my hand this 26th day of February, 1906, in the presence of two attesting witnesses.

JOHN F. ov JoY.

Witnesses:

P. T. DODGE, E. J. LAMB. 

